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Diffstat (limited to 'arch/um/drivers/cow_user.c')
-rw-r--r--arch/um/drivers/cow_user.c133
1 files changed, 65 insertions, 68 deletions
diff --git a/arch/um/drivers/cow_user.c b/arch/um/drivers/cow_user.c
index 0ec4052db9c5..93f227a25ba4 100644
--- a/arch/um/drivers/cow_user.c
+++ b/arch/um/drivers/cow_user.c
@@ -1,17 +1,18 @@
-#include <stddef.h>
-#include <string.h>
-#include <errno.h>
-/* _XOPEN_SOURCE is needed for pread, but we define _GNU_SOURCE, which defines
+/*
+ * Copyright (C) 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
+ * Licensed under the GPL
+ */
+
+/*
+ * _XOPEN_SOURCE is needed for pread, but we define _GNU_SOURCE, which defines
* that.
*/
#include <unistd.h>
#include <byteswap.h>
-#include <sys/time.h>
-#include <sys/param.h>
-#include <sys/user.h>
-
-#include "os.h"
-
+#include <errno.h>
+#include <string.h>
+#include <arpa/inet.h>
+#include <asm/types.h>
#include "cow.h"
#include "cow_sys.h"
@@ -28,7 +29,8 @@ struct cow_header_v1 {
__s32 sectorsize;
} __attribute__((packed));
-/* Define PATH_LEN_V3 as the usual value of MAXPATHLEN, just hard-code it in
+/*
+ * Define PATH_LEN_V3 as the usual value of MAXPATHLEN, just hard-code it in
* case other systems have different values for MAXPATHLEN.
*
* The same must hold for V2 - we want file format compatibility, not anything
@@ -46,7 +48,8 @@ struct cow_header_v2 {
__s32 sectorsize;
} __attribute__((packed));
-/* Changes from V2 -
+/*
+ * Changes from V2 -
* PATH_LEN_V3 as described above
* Explicitly specify field bit lengths for systems with different
* lengths for the usual C types. Not sure whether char or
@@ -70,7 +73,8 @@ struct cow_header_v2 {
* Fixed (finally!) the rounding bug
*/
-/* Until Dec2005, __attribute__((packed)) was left out from the below
+/*
+ * Until Dec2005, __attribute__((packed)) was left out from the below
* definition, leading on 64-bit systems to 4 bytes of padding after mtime, to
* align size to 8-byte alignment. This shifted all fields above (no padding
* was present on 32-bit, no other padding was added).
@@ -122,7 +126,7 @@ void cow_sizes(int version, __u64 size, int sectorsize, int align,
int bitmap_offset, unsigned long *bitmap_len_out,
int *data_offset_out)
{
- if(version < 3){
+ if (version < 3) {
*bitmap_len_out = (size + sectorsize - 1) / (8 * sectorsize);
*data_offset_out = bitmap_offset + *bitmap_len_out;
@@ -144,46 +148,46 @@ static int absolutize(char *to, int size, char *from)
char save_cwd[256], *slash;
int remaining;
- if(getcwd(save_cwd, sizeof(save_cwd)) == NULL) {
+ if (getcwd(save_cwd, sizeof(save_cwd)) == NULL) {
cow_printf("absolutize : unable to get cwd - errno = %d\n",
errno);
- return(-1);
+ return -1;
}
slash = strrchr(from, '/');
- if(slash != NULL){
+ if (slash != NULL) {
*slash = '\0';
- if(chdir(from)){
+ if (chdir(from)) {
*slash = '/';
cow_printf("absolutize : Can't cd to '%s' - "
"errno = %d\n", from, errno);
- return(-1);
+ return -1;
}
*slash = '/';
- if(getcwd(to, size) == NULL){
+ if (getcwd(to, size) == NULL) {
cow_printf("absolutize : unable to get cwd of '%s' - "
"errno = %d\n", from, errno);
- return(-1);
+ return -1;
}
remaining = size - strlen(to);
- if(strlen(slash) + 1 > remaining){
+ if (strlen(slash) + 1 > remaining) {
cow_printf("absolutize : unable to fit '%s' into %d "
"chars\n", from, size);
- return(-1);
+ return -1;
}
strcat(to, slash);
}
else {
- if(strlen(save_cwd) + 1 + strlen(from) + 1 > size){
+ if (strlen(save_cwd) + 1 + strlen(from) + 1 > size) {
cow_printf("absolutize : unable to fit '%s' into %d "
"chars\n", from, size);
- return(-1);
+ return -1;
}
strcpy(to, save_cwd);
strcat(to, "/");
strcat(to, from);
}
chdir(save_cwd);
- return(0);
+ return 0;
}
int write_cow_header(char *cow_file, int fd, char *backing_file,
@@ -194,22 +198,23 @@ int write_cow_header(char *cow_file, int fd, char *backing_file,
int err;
err = cow_seek_file(fd, 0);
- if(err < 0){
+ if (err < 0) {
cow_printf("write_cow_header - lseek failed, err = %d\n", -err);
goto out;
}
err = -ENOMEM;
header = cow_malloc(sizeof(*header));
- if(header == NULL){
- cow_printf("write_cow_header - failed to allocate COW V3 header\n");
+ if (header == NULL) {
+ cow_printf("write_cow_header - failed to allocate COW V3 "
+ "header\n");
goto out;
}
header->magic = htonl(COW_MAGIC);
header->version = htonl(COW_VERSION);
err = -EINVAL;
- if(strlen(backing_file) > sizeof(header->backing_file) - 1){
+ if (strlen(backing_file) > sizeof(header->backing_file) - 1) {
/* Below, %zd is for a size_t value */
cow_printf("Backing file name \"%s\" is too long - names are "
"limited to %zd characters\n", backing_file,
@@ -217,12 +222,12 @@ int write_cow_header(char *cow_file, int fd, char *backing_file,
goto out_free;
}
- if(absolutize(header->backing_file, sizeof(header->backing_file),
+ if (absolutize(header->backing_file, sizeof(header->backing_file),
backing_file))
goto out_free;
err = os_file_modtime(header->backing_file, &modtime);
- if(err < 0){
+ if (err < 0) {
cow_printf("write_cow_header - backing file '%s' mtime "
"request failed, err = %d\n", header->backing_file,
-err);
@@ -230,7 +235,7 @@ int write_cow_header(char *cow_file, int fd, char *backing_file,
}
err = cow_file_size(header->backing_file, size);
- if(err < 0){
+ if (err < 0) {
cow_printf("write_cow_header - couldn't get size of "
"backing file '%s', err = %d\n",
header->backing_file, -err);
@@ -244,7 +249,7 @@ int write_cow_header(char *cow_file, int fd, char *backing_file,
header->cow_format = COW_BITMAP;
err = cow_write_file(fd, header, sizeof(*header));
- if(err != sizeof(*header)){
+ if (err != sizeof(*header)) {
cow_printf("write_cow_header - write of header to "
"new COW file '%s' failed, err = %d\n", cow_file,
-err);
@@ -254,14 +259,14 @@ int write_cow_header(char *cow_file, int fd, char *backing_file,
out_free:
cow_free(header);
out:
- return(err);
+ return err;
}
int file_reader(__u64 offset, char *buf, int len, void *arg)
{
int fd = *((int *) arg);
- return(pread(fd, buf, len, offset));
+ return pread(fd, buf, len, offset);
}
/* XXX Need to sanity-check the values read from the header */
@@ -278,31 +283,29 @@ int read_cow_header(int (*reader)(__u64, char *, int, void *), void *arg,
unsigned long version, magic;
header = cow_malloc(sizeof(*header));
- if(header == NULL){
+ if (header == NULL) {
cow_printf("read_cow_header - Failed to allocate header\n");
- return(-ENOMEM);
+ return -ENOMEM;
}
err = -EINVAL;
n = (*reader)(0, (char *) header, sizeof(*header), arg);
- if(n < offsetof(typeof(header->v1), backing_file)){
+ if (n < offsetof(typeof(header->v1), backing_file)) {
cow_printf("read_cow_header - short header\n");
goto out;
}
magic = header->v1.magic;
- if(magic == COW_MAGIC) {
+ if (magic == COW_MAGIC)
version = header->v1.version;
- }
- else if(magic == ntohl(COW_MAGIC)){
+ else if (magic == ntohl(COW_MAGIC))
version = ntohl(header->v1.version);
- }
/* No error printed because the non-COW case comes through here */
else goto out;
*version_out = version;
- if(version == 1){
- if(n < sizeof(header->v1)){
+ if (version == 1) {
+ if (n < sizeof(header->v1)) {
cow_printf("read_cow_header - failed to read V1 "
"header\n");
goto out;
@@ -314,8 +317,8 @@ int read_cow_header(int (*reader)(__u64, char *, int, void *), void *arg,
*align_out = *sectorsize_out;
file = header->v1.backing_file;
}
- else if(version == 2){
- if(n < sizeof(header->v2)){
+ else if (version == 2) {
+ if (n < sizeof(header->v2)) {
cow_printf("read_cow_header - failed to read V2 "
"header\n");
goto out;
@@ -328,8 +331,8 @@ int read_cow_header(int (*reader)(__u64, char *, int, void *), void *arg,
file = header->v2.backing_file;
}
/* This is very subtle - see above at union cow_header definition */
- else if(version == 3 && (*((int*)header->v3.backing_file) != 0)){
- if(n < sizeof(header->v3)){
+ else if (version == 3 && (*((int*)header->v3.backing_file) != 0)) {
+ if (n < sizeof(header->v3)) {
cow_printf("read_cow_header - failed to read V3 "
"header\n");
goto out;
@@ -345,17 +348,18 @@ int read_cow_header(int (*reader)(__u64, char *, int, void *), void *arg,
*bitmap_offset_out = ROUND_UP(sizeof(header->v3), *align_out);
file = header->v3.backing_file;
}
- else if(version == 3){
+ else if (version == 3) {
cow_printf("read_cow_header - broken V3 file with"
" 64-bit layout - recovering content.\n");
- if(n < sizeof(header->v3_b)){
+ if (n < sizeof(header->v3_b)) {
cow_printf("read_cow_header - failed to read V3 "
"header\n");
goto out;
}
- /* this was used until Dec2005 - 64bits are needed to represent
+ /*
+ * this was used until Dec2005 - 64bits are needed to represent
* 2038+. I.e. we can safely do this truncating cast.
*
* Additionally, we must use ntohl() instead of ntohll(), since
@@ -381,7 +385,7 @@ int read_cow_header(int (*reader)(__u64, char *, int, void *), void *arg,
}
err = -ENOMEM;
*backing_file_out = cow_strdup(file);
- if(*backing_file_out == NULL){
+ if (*backing_file_out == NULL) {
cow_printf("read_cow_header - failed to allocate backing "
"file\n");
goto out;
@@ -389,7 +393,7 @@ int read_cow_header(int (*reader)(__u64, char *, int, void *), void *arg,
err = 0;
out:
cow_free(header);
- return(err);
+ return err;
}
int init_cow_file(int fd, char *cow_file, char *backing_file, int sectorsize,
@@ -402,7 +406,7 @@ int init_cow_file(int fd, char *cow_file, char *backing_file, int sectorsize,
err = write_cow_header(cow_file, fd, backing_file, sectorsize,
alignment, &size);
- if(err)
+ if (err)
goto out;
*bitmap_offset_out = ROUND_UP(sizeof(struct cow_header_v3), alignment);
@@ -411,17 +415,18 @@ int init_cow_file(int fd, char *cow_file, char *backing_file, int sectorsize,
offset = *data_offset_out + size - sizeof(zero);
err = cow_seek_file(fd, offset);
- if(err < 0){
+ if (err < 0) {
cow_printf("cow bitmap lseek failed : err = %d\n", -err);
goto out;
}
- /* does not really matter how much we write it is just to set EOF
+ /*
+ * does not really matter how much we write it is just to set EOF
* this also sets the entire COW bitmap
* to zero without having to allocate it
*/
err = cow_write_file(fd, &zero, sizeof(zero));
- if(err != sizeof(zero)){
+ if (err != sizeof(zero)) {
cow_printf("Write of bitmap to new COW file '%s' failed, "
"err = %d\n", cow_file, -err);
if (err >= 0)
@@ -429,15 +434,7 @@ int init_cow_file(int fd, char *cow_file, char *backing_file, int sectorsize,
goto out;
}
- return(0);
-
+ return 0;
out:
- return(err);
+ return err;
}
-
-/*
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-25 01:48:52 +0000